TF-888 Remove duplicate string

lib/features/manage_account/presentation/email_rules/widgets/email_rules_header_widget.dart

@@ -33,7 +33,7 @@ class EmailRulesHeaderWidget extends StatelessWidget {
                 fontWeight: FontWeight.bold,
                 color: Colors.black)),
         const SizedBox(height: 4),
-        Text(AppLocalizations.of(context).emailRulesSubtitle,
+        Text(AppLocalizations.of(context).emailRuleSettingExplanation,
             style: const TextStyle(
                 fontSize: 15,
                 fontWeight: FontWeight.normal,

lib/l10n/intl_messages.arb

@@ -1,5 +1,5 @@
 {
-  "@@last_modified": "2022-09-08T15:46:55.686024",
+  "@@last_modified": "2022-09-09T11:02:43.750933",
   "initializing_data": "Initializing data...",
   "@initializing_data": {
     "type": "text",
@@ -1762,12 +1762,6 @@
     "placeholders_order": [],
     "placeholders": {}
   },
-  "emailRulesSubtitle": "Creating rules to handle incoming messages. You choose both the condition that triggers a rule and the actions the rule will take.",
-  "@emailRulesSubtitle": {
-    "type": "text",
-    "placeholders_order": [],
-    "placeholders": {}
-  },
   "addNewRule": "Add rule",
   "@addNewRule": {
     "type": "text",

lib/main/localizations/app_localizations.dart

@@ -1806,13 +1806,6 @@ class AppLocalizations {
     );
   }
 
-  String get emailRulesSubtitle {
-    return Intl.message(
-      'Creating rules to handle incoming messages. You choose both the condition that triggers a rule and the actions the rule will take.',
-      name: 'emailRulesSubtitle',
-    );
-  }
-
   String get addNewRule {
     return Intl.message(
       'Add rule',